The present invention relates generally to printing devices, and particularly to label-making printers.
A label includes print imaging and an adhesive surface. The print imaging typically represents some text or graphic content identifying, characterizing, quantifying, or otherwise referencing some article. Labels on consumer items contain bar codes for inventory control, price information, or, generally, to identify characteristics of the goods or the source of such goods. Labels on food items, for example, contain images, such as text or graphics, that describe or portray the product. Currently, labels find limited application in other more creative and personal applications. For example, labels may be decorative as applied to gifts or packaging. Conventional label making methods and label-media fall short, however, of the potential for labels as a convenient, i.e., easily produced and used, device presenting selected print imaging for display on a contact surface.
The bulk of conventional home, small office, and personal printing involves application of text and images on sheet-form media. Most typically, the sheet-form media is paper, e.g., 8xc2xd by 11 inch sheets. Other media sizes include envelope sizes, card stock sizes, and other conventional paper sizes, e.g., A-4 paper size. Accordingly, conventional printers include paper transport and print head arrangements particularly adapted for such media sizes. Most printers allow media size variation by multiple source trays, by modification in paper tray compartments and by front-fed arrangements. A user thereby applies print imaging to such variety of paper sizes from small card stock to large sheet-form media.
Unfortunately, most printers have a lower limit on the size of media carried by the paper transport mechanism and print head operation in relation thereto. For many applications, e.g., from printing postcards to envelopes to sheet-form media, this lower boundary in media size represents no problem.
Print imaging on a label typically appears on the upper-most surface of the label. Since the image is exposed, it is vulnerable to moisture and scuffing, which degrade the quality of the image. In some commercial applications, the image is protected by applying a clear film over the image. When a printed label is applied to the item, a border is created because the label is thick and does not blend into the background of the item. This commonly happens, for example, when a white label is applied to a colored background. While aesthetic concerns are not an issue in all applications, aesthetics are important when the user wants the labeled item to look professional or when labels are used in more creative and artistic applications. In some applications, images are printed onto transparent labels so that the label blends into the background of the item. However, the print is located on the upper surface of the label and is, therefore, still exposed to moisture and scuffing. For home uses, the image may be laminated to protect it from moisture and scuffing. However, this approach is disadvantageous since lamination increases the overall thickness of the image, adds additional steps to the process, and requires a laminating device.
Label-making printing operations present challenge, therefore, with respect to conventional printer operation. Individual labels, in many cases, are smaller than the typical lower size limit manageable by most printers. In other words, printers are typically not adapted to handle especially small media sizes and, therefore, are not well suited for printing on individual labels. Several approaches to label-making have evolved to overcome this challenge.
First, because conventional printers are most suitably adapted for sheet-form media, e.g., 8xc2xd by 11 inch sheets, labels often come as an array of labels grouped together on an 8xc2xd by 11 inch sheet. Typically, such label sheets include a waxy back sheet to which the labels adhere. As such, most printers accept and transport past a printing zone a sheet of labels and apply appropriate text and graphics thereto. Unfortunately, the user must pass through the printer an entire sheet of labels even when only a single label is required. In other words, the user sends through the printer the entire label sheet for the sake of printing a single label. While in some applications it is possible to make use of all labels on the sheet, this presents certain inconvenience and inefficiency when a user wishes to produce fewer than an entire sheet of labels. Once a user sends a label sheet through a printer and removes one or more labels, it is generally unadvisable to send the label sheet back through the printer with one or more labels removed from the back sheet. Although some special label sheets have been proposed allowing multiple passes through a printer, such use presents risk of contamination within the printer paper transport and printing system when exposed to the waxy back sheet.
Second, printers have evolved as dedicated label-making printers. These label-making printers are small printers having the capability of printing individual labels. Unfortunately, such dedicated label-making printers, while capable of printing single labels at a time, are limited in the size of labels produced. In other words, the labels are of fixed or bordered size and printing applications must adapt to this limited size when producing labels. Furthermore, such printers are generally incapable of producing graphics or color image presentation. Accordingly, dedicated label-making printers do provide advantage in their ability to produce single labels but suffer from limited output capabilities in terms of size and image presentation.
In any case, label making presents certain challenge or additional effort, especially when the labels are relatively small. It would be desirable, therefore, to more conveniently produce labels, i.e., media bearing print imaging and an adhesive surface.
Other known label making methods involve using inkjet receptor compositions suitable for coating onto plastics to make the plastics inkjet receptive. For example, applications for overhead transparencies are known in the art. These are composed of transparent plastic materials such as polyester, which alone will not accept the aqueous inks and are therefore coated with receptor layers. Typically these receptor layers are composed of mixtures of water soluble polymers which can absorb the aqueous mixture from which the inkjet ink comprises, such as hydrophilic layers having poly (vinyl pyrrolidone) or poly (vinyl alcohol), as described in U.S. Pat. Nos. 4,379,804; 4,903,041; and 4,904,519. Also known are methods of cross-linking hydrophilic polymers in the receptor layers as disclosed in U.S. Pat. Nos. 4,649,064; 5,141,797; 5,023,129; 5,208,092; and 5,212,008. Other coating compositions contain water-absorbing particulates such as inorganic oxides, as disclosed in U.S. Pat. Nos. 5,084,338; 5,023,129; and 5,002,825, or those containing particulates, such as cornstarch, as disclosed in U.S. Pat. Nos. 4,935,307 and 5,302,437.
Many of these types of inkjet receptor media, however, are less than ideal for image graphics because they include water-sensitive polymer layers. Even if subsequently overlaminated, they still contain a water-soluble or water-swellable layer, which, in time, can be subject to extraction with water and can lead to damage of the graphic and liftoff of the overlaminate. Additionally, some of the common constituents of these hydrophilic coatings contain water-soluble polymers not ideally suitable to the heat and UV exposures experienced in exterior environments, thus limiting their exterior durability. Finally, the drying rate after printing of these materials appears slow since until dry, the coating is plasticized or even partially dissolved by the ink solvents (mainly water) so that the image can be easily damaged and can be tacky before it is dry.
In the commercial setting, labels are printed by a number of processes known in the art, such as screen printing, thermal transfer printing, and inkjet printing. These processes vary dramatically in cost and the resolution of the printed images that are produced. Screen printing and thermal transfer printing are typically limited to commercial applications because they produce large numbers of identical labels and require use of expensive equipment. Screen printing is commonly used to print the transparent labels, such as those used on electronics and appliances. While the images may be screen-printed onto the reverse side of a transparent label, the adhesive is applied after the image is printed, which adds an additional step to the process, making it impractical or cost prohibitive for low-volume, non-commercial, or personal use.
Thermal transfer printing is a contact printing process where a thermally reactive ribbon is located between a thermal print head and a print media onto which the image is to be printed. The print head contains heating elements that are selectively energized. As the ribbon is heated, ink is transferred from the ribbon to the print media to create the printed image. Images created by thermal transfer printing are located on the upper surface of the media and are, therefore, vulnerable to moisture and scuffing. The higher cost of thermal transfer printers makes it economically impractical for use as personal printers.
An exemplary type of thermal transfer printer is a label printer. Label printers are commonly used in grocery stores to label food items with transparent labels. An exemplary Label printer is disclosed in U.S. Pat. No. 4,927,278 issued to Kuzuya et al. Label printers currently available on the market include products by Kroy LLC and Zebra Technologies.
Inkjet printers have come into general use for wide-format electronic printing for a broad and varied range of applications. Because of the simplicity of operation and economy of inkjet printers, this printing process holds a superior growth potential promise for the printing industry to produce wide format, image on demand, presentation quality graphics. The components of an inkjet system used for making graphics can be grouped into three major categories: 1) computer, software, printer; 2) ink; and 3) receptor medium. The computer, software, and printer will control the size, number and placement of the ink drops and will transport the receptor medium through the printer. The ink will contain the colorant which forms the image and carrier for that colorant. The receptor medium provides the repository which accepts and holds the ink. The quality of the inkjet image is a function of the total system. However, the composition and interaction between the ink and receptor medium is most important in an inkjet system.
Inkjet printers are commonly purchased as personal printers because they are easy to use, produce high quality, color images, and are less expensive than thermal transfer printers. Inkjet printers are also available in a variety of formats that allow the user to print professional-looking banners or conventional labels at home. Ink-jet printing is a non-contact printing process in which droplets of ink are deposited on a print media. In response to electrical signals generated by a microprocessor, fine droplets of ink are ejected onto print media such as paper, transparency film, or textiles. The ejection of ink droplets in a particular order forms alphanumeric characters, area fills, and other patterns on the print media. Images are printed onto many types of media including paper or transparent, plastic receptor media such as transparent labels or overhead transparencies. However, inkjet inks compositions are substantially aqueous-based and do not adhere to the inherently hydrophobic surface of plastic receptor media. Therefore, to print images onto plastic receptor media, these media must first be coated with a hydrophilic film to improve its affinity for the inkjet ink. The image is printed on top of the hydrophilic film, however, and not protected from moisture and scuffing.
Thus, labels are typically be applied to a contact surface for display purposes and such positioning presents risk of smudging or damage to the text or graphics thereon. In other words, frequently labels are applied in areas exposed to abrasive contact or other such environmental degradation. Certain printing methods, e.g., inkjet printing methods, can be susceptible to smudging or degradation due to abrasion.
It would be desirable, therefore, to provide a convenient label-making media and label-making printer having greater flexibility in the size of labels produced as well as a capability of producing both images and text across a variety of fonts and colors with protection against degradation in use thereof. The subject matter of the present invention provides such a label-making printer.
The present invention proposes application of print imaging to the adhesive portion of a label. As a result, such print imaging is captured between the body of the label and a contact surface to which the label adheres. Media under the present invention may be provided in cartridge form including an encoding device reporting movement of the media. In one aspect of the present invention, media may take the form of adhesive tape and be deployed from a printer under the present invention taking generally the form of a tape dispenser. In one aspect of the present invention, such printer may react to manual deployment of tape by application of print imaging. In another aspect of the invention, a motorized printer applies print imaging to an adhesive surface of a label carried therepast and presented for collection by a user. Use of a detector to report movement of tape media under the present invention provides basis for metering of print imaging onto an adhesive.
The subject matter of the present invention is particularly pointed out and distinctly claimed in the concluding portion of this specification. However, both the organization and method of operation of the invention, together with further advantages and objects thereof, may best be understood by reference to the following description taken with the accompanying drawings wherein like reference characters refer to like elements.